The effect of autogenous cancellous bone grafts on gealing of experimental furcation defects in dogs

Chronic, through-and-through, furcation defects were created in mandibular premolars of six beagle dogs. These defects were surgically treated without autogenous, cancellous, bone grafts. Healing sockets in the maxilla serged as donor sites. Block specimens were removed after eight weeks. All teeth from all dogs showed some reattachment after treartment as evidenced by newly formed cementum. None of the specimens showed complete regeneration, i.e.a periodontal membrane with new cementum all aroune the fornix of the furcation. Histometric measurements showed that the use of osseous grafts did not improve the results in the present experimental model.     

Open versus laparoscopic cholecystectomy for gallbladder carcinoma

Laparoscopic surgery has replaced conventional open cholecystectomy for benign gallbladder disease. A major concern is how to handle gallbladder cancer in the laparoscopic era, since there are numerous case reports of port site metastases from gallbladder cancer after laparoscopic cholecystectomy. There are also many experimental studies favoring the opinion that the laparoscopic technique implies a higher risk of spreading malignant disease. This opinion has gained wide acceptance despite little previous clinical effort to determine the risk of tumor dissemination and the lack of comparisons between open and laparoscopic surgery. This report is a short summary of our own studies and present knowledge with special respect to the clinical aspects of the development and incidence of abdominal wall metastases. Among 270 patients with verified gallbladder carcinoma in whom 210 had open surgery and 60 a laparoscopic cholecystectomy, 12 patients (6.5%) in the open cholecystectomy group and 9 (15%) in the laparoscopic group developed incisional metastases. Although the sparse clinical documentation does not unavoidably mean that laparoscopic cholecystectomy has an increased risk of disseminating tumor cells, we recommend open surgery in cases of known or suspected gallbladder carcinoma.     

Studies on the identity of the rat optic nerve transmitter

The possible role of glutamate, aspartate, sulfur-containing excitatory amino acids and γ-glutamyl peptides as major transmitters in the rat optic nerve was evaluated. Four days following optic nerve lesion the K⁺-evoked Ca⁺-dependent glutamate release was reduced to 31 ± 16% (±S.D., n = 9) comparing release from slices of the denervated (contralateral to the lesion) and non-denervated (ipsilateral) superior colliculus, indicative of a major transmitter function for glutamate. However, significant decreases in glutamate release could not be detected seven days following the lesion (n = 5). Other studies have shown that optic nerve denervation induce formation of synapses of non-retinal origin and cause other cellular changes which may reduce the effect of deafferentation on glutamate release after 7 days. No significant change was observed in aspartate release following the lesion. The concentrations of cysteine sulfinate, cysteate, homocysteine sulfinate, homocysteate and O-sulfo-serine in the optic layers of the superior colliculus were below 1 nmol/g tissue (n = 6). Theoretical considerations indicate that this level is too low for a function of any of these as a major optic nerve transmitter. All postsynaptic components in the rat superior colliculus response, evoked by electrical optic nerve stimulation, were reduced by kynurenate (1–10 mM), a broad spectrum glutamate-receptor antagonist. The study gives further support for the view that glutamate is a major transmitter in the rat optic nerve.     

Parity among atopic and non-atopic mothers

A temporary Th2 skewed immunity is essential for a successful outcome of pregnancy. It is also a hallmark of atopic disease. We recorded the number of siblings to 3667 children in relation to maternal atopy. In all, 65% of the allergic and 56% of the non-allergic mothers had more than one child (p < 0.001). These data support a hypothesis that the atopic genotype may be associated with an increased likelihood for a successful outcome of pregnancy and thus from an evolutionary point of view compensate for the less efficient host defence against microbial infections associated with this type of immunity.